FAIRFAX (CBS SF) — A rabid bat was found near Lake Lagunitas in Marin County over the Labor Day holiday weekend, a Marin Humane Society spokeswoman said Friday.

A passerby found the bat in the main parking lot of the lake south of Fairfax on Labor Day, Marin Humane Society spokeswoman Carrie Harrington said.

The concerned citizen noticed the bat wasn’t acting normally and was screeching, so the person collected the animal in a hat and brought it to the WildCare wildlife rehabilitation center in San Rafael, Harrington said.

The person did not touch the bat, she said.

WildCare staff turned the bat over to the Marin Humane Society, which works with the Marin County Department of Health and Human Services. Health officials tested the bat, which had been euthanized, and found it tested positive for rabies.

Rabies is a viral infection that can be spread from species to species and causes inflammation of the brain.

The humane society has since issued an alert for any people and dogs that were in the Lake Lagunitas area recently and possibly came in contact with any bats.

Anyone who had physical contact with a bat or who noticed their dog sniffing around an unknown area of the lake where bats may reside is asked to call the health department or humane society at (415) 473-4163 or (415) 883-4621, ext. 420, respectively.

The bat was the first confirmed case of rabies in Marin County this year, Harrington said.

Melanie Piazza, the director of animal care at WildCare, said rabies is not a major problem in the West Coast or California in particular, but said “it is something people should be aware of.”

She noted bats are the animals mostly of concern for rabies in Marin County and that residents should never pick up a bat or any wild animals.

Bats are “incredibly important to our ecosystem,” and eat hordes of insects, keeping things in balance, Piazza said. She added that bats never attack humans unless provoked.

As for pets, Piazza encouraged owners out with dogs to keep the animals on leash to avoid contact with wild or sick animals.

Rabies vaccines are also crucial in protecting pets and are available for humans who believe they are at high risk of contracting the potentially fatal infection.

(Copyright 2012 by CBS San Francisco and Bay City News Service. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)